Multiple fuse



NOV.'20, 1934. M. UPSEY 1,981,735

MULTIPLE FUS E Filed NOV. 13, 1933 Fig. 2.

Fig.4. Fig.5.

IN VENTOIQI MA UR/CE L/Psm;

6 6 r 7 Arm/ Na Patented Nov. 20, 1934 UNITE STATES MULTIPLE FUSE Maurice Lipsey, Glasgow, Scotland, assignor of one-half to British National Electrics Limited,

Mossend, Scotland Application November 13, 1933, Serial No. 697,819 In Great Britain November 29, 1932 6 Claims.

This invention relates to a multiple fuse for an electric circuit, of the type having a plurality of separate fuse elements, and in which, when a fuse element is blown a new one can be brought into circuit by effecting relative movement between the fuse elements and selecting means. Disadvantages in some of the existing types of multiple fuses lie firstly in the fact that a considerable amount of time and trouble is necessary to renew the same and secondly that a considerable amount of noise and smoke results from the burning of the fuse element. The chief object of the present invention is to overcome these disadvantages and to provide a multiple fuse in which burnt out fuse elements may easily be replaced and in fact may be sold separately as accessories therefor.

According to the present invention a multiple fuse for an electric circuit, comprises, an easily replaceable fuse magazine, a plurality of closed passages in the body of said magazine, a plurality of separate fuse elements which are fixedly located in said closed passages, contact members at the ends of said passages, the whole fuse magazine being assembled as an integral unit, and selector means in the electric circuit and co-opcrating with the said contact members, relative movement between the magazine and the selector means serving to put any of the fuses into or out of circuit. a 7

As a result of the present invention when all the fuse elements have been burnt the entire magazine may easily be removed and thrown away and a fresh one quickly fitted in place.

0 These fresh ones may be marketed separately and as accessories by the makers.

I will now describe embodiments of my invention, simply by way of example, with reference to the accompanying drawing, whereonz- Fig. 1- is a plan view of a multiple fuse in accordance with the present invention.

Fig. 2 is a plan view corresponding to Fig. 1, but with the cover removed and showing the fuse magazine.

Fig. 3 is a cross sectional elevation on the line III-III, Fig. 1, but drawn to an enlarged scale.

Figs. 4 and 5 are views similar to Fig. 3, but of modifications.

The multiple fuse shown in Figs. 1-3 comprises a base 1 with a circular contact member 2 having a radially extending arm 2a connected to a terminal 3 which is connected to one end of the external electric circuit. The other end of the external circuit is connected to a terminal 4 which is connected, through a copper strip 5, with a central upstanding contact pillar 6 of electrically conducting material, and of square or rectangular cross-section. The fuse magazine '7 is of cylindical shape and is formed of electrically insulating material, for example of moulded synthetic resin material or porcelain and is provided with six longitudinal passages 8 within which the fuse elements 9 are located. The magazine itself thus serves to insulate the individual fuse elements. In order, however, to ensure efficient damping of the fusing explosion each of these passages 8 is closed at the top end by means of copper contact discs 10 to which the fuse elements are soldered or otherwise secured, while at the lower end of each passage the fuse element is soldered or otherwise secured to a common contact ring 11 having small knobs or projections 11a to ensure good contact. The interior of each passage is filled with silver sand or other explosion damping material, and the contact members 10 and 11 serve substantially to seal the passages and enclose the fuse elements so that when a fuse burns out or fuses no flash or smoke is apparent, and very little, if any, sound is audible.

The magazine 7 has a central axial passage 12 which is of square cross section at the lower part 12a, corresponding to the shape of the pillar 6 in order to prevent rotation thereon, and of circular cross section at the upper part 12?). The magazine is enclosed by a cover 13 mounted on the top of which is a rotary indicator 14 which is numbered to correspond to the six different fuse elements, a co-operating index arrow 18 being provided on the cover. The indicator 14 also carries on its underside a radially extending resilient contact arm 15 which, when the indicator is turned comes into engagement with any one of the contact discs 10. A split contact pin 16 also extends downwardly from said indicator and is connected with said contact arm, the lower end of said pin engaging an interior passage in the pillar 6.

It will thus be evident that the circuit between the two terminals 3 and 4 is completed through strip 5 the central pillar 6, the pin 16, contact arm 15, the selected fuse element 9, the contact ring 11, and the contact 2.

An aperture 1'7 is provided at each end of the cover 13 for entry of the conductors from the exterior circuit, while holes 19 are provided in the base for securing it to the fuse box or other fixture on which the multiple fuse is mounted.

It will be evident that when all the fuse elements in a magazine have been blown, the magazine may easily be removed and replaced by a new one.

The construction shown in Fig. 4 is somewhat similar to that shown in Fig. 3, and the external circuit is completed through terminal 35, conductor 36, rotary pillar 37 rotary switch blade 38 mounted on said pillar 3'7, one of the six spring contacts 39 secured to the removable cover 45, fuse element 40, one of the contact studs 40a, and fixed ring contact 41 to the other terminal 42. Any fuse element is put into or out of circuit by rotation of a knob 43 which is secured to the rotary pillar 3'7, the magazine 44 being nonrotatable owing to two diametrally opposite squared parts on the magazine side which engage corresponding parts on the interior of the cover at 45a.

To replace a used magazine the cover 45 together with the knob 43, pillar 3'7 and old magazine 44, are removed, a fresh magazine is inserted and the cover and associated parts replaced.

In the construction shown in Fig. 5 the cylindrical fuse magazine 20 carries fuse elements 21 within passages 22 said elements being surrounded by silver sand or other explosion' damping material. The upper end of each passage is closed by a contact disc or member 23 and the lower end by a contact disc or member 24. The base 25 is of electrically insulating material and carries a central upwardly extending contact pillar 26 connected with the terminal 28 through a copper strip 27?). The magazine 20 is rotatably mounted on this pillar, and a brass spider 27a mounted on said magazine contacts with the top of said pillar and completes the circuit to each of the fuse elements 21. A rotary knob 29 is mounted on the top of the cover 30 and .by means of the rotary blade 29a which engages the spider 27a is adapted to rotate the magazine 20. The circuit to the other terminal 31 is completed through a fixed contact 32 adapted to be engaged by any one of the disc contacts 24, while a spring 33 presses the magazine into contact with the same.

As aforesaid, owing to the fact that each of the fuse elements is surrouded by sand or other explosion damping material and the ends of the fuse passage are sealed, when the fuse blows no flash. becomes visible and little, if any, explosion sound is heard.

The multiple fuse described above can also be utilized as a switch when necessary, as, in order to open the circuit it is only necessary to switch one of the already blown fuses. or a dummy fuse into circuit.

I claim:-

1. A multiple fuse for an electric circuit con. prising, a non-rotatable but removable fuse magazine, a plurality of separate fuse elements each enclosed and sealed permanently in and integral with said magazine, a stationary upright pillar zine the lower part of which passage is of noncircular cross section corresponding to that of the said pillar and engages the same so as to prevent rotation of the magazine.

2. A multiple fuse for an electric circuit, comprising, a non-rotatable but removable fuse magazine, a plurality of entirely separate fuseelements permanently enclosed within said magazine each insulated from the next and surrounded by explosion-damping material, the whole fuse magazine being made as an integral unit, a removable cover for said fuse magazine, a rotary member mounted on said cover, rotary contact means operated by said member and adapted to put any of said fuse elements into or out of circuit, and inter-engaging parts on the magazine and the cover which prevent rotation of the former but allow removal of the cover and the magazine separately.

3. A multiple fuse for an electric circuit comprising, a base, a removable fuse magazine nonrotatably mounted on said base, a plurality of longitudinally extending insulated channels in said magazine, a fuse element permanently and integrally sealed in place in each of said channels and surrounded by explosion-damping material therein, ,a contact at each end of each of said channels and to which said fuse elements are secured, said contacts serving to seal the fuse elements in said channels, a removable unitary cover enclosing said magazine, a rotary indicator mounted on said cover and operating a contact member adapted to move over the fuse contacts at the top of the magazine and put any one of the fuse elements into or out of circuit.

4. A multiple fuse for an electric circuit comprising, an easily removable fuse magazine, a plurality of passages in said magazine, a plurality of fuse elements located separately in said passages and insulated from each other, the whole fuse magazine-being assembled as an integral unit, an insulating base, an upright electrically conductive pillar mounted on said base, a cover mounted on said base and extending over said magazine, electrically conductive means extending across the top of said magazine and electrically connecting said magazine to said pillar, a fixed contact member connected with said electric circuit and adapted to engage the lower end of the magazine and the lower ends of the fuse elements, rotary operating means extending through said cover and adapted to engage said conductive means in order to rotate the magazine relative to said fixed contact thereby putting any one of the fuses into or out of the electric circult.

5. A multiple fuse for an electric circuit comprising in combination, a fiat base, a non-rotatable but removable fuse magazine mounted over said base, a plurality of separate fuse elements permanently sealed within said magazine, said fuse elements each being surrounded by fine granular explosion-damping material, the whole fuse magazine being made up as an integral and replaceable unit, terminals mounted on said base alongside said fuse magazine for connecting the multiple fuse to said electric circuit, a removable cover adapted to fit over said base and enclose said magazine and said terminals. and rotary selector means operated exteriorly of said 1 11- terial, and relatively movable means operating circularly about said central member for successively establishing connection with a selected one of said fuse elements.

, MAURICE LIPSEY. 

